DaemonUmbra

Can you be more specific? Does the launcher itself just go black or does it launch a blacked out game?

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This is an issue with your installation of Windows. Although yours appears to be corrupted rather than missing, follow these steps: https://answers.microsoft.com/en-us/windows/forum/games_windows_10/d3d9dll-is-missing/7f594fda-3455-41e8-98c4-7dc3b786660e

Show the full path of the file you deleted, please

Go into the save and delete serverconfig/forge-server.toml

What command did you use? If I recall correctly OSX should use the Unix-like script that has no extension

I don't see how being required to use a specific computer for schoolwork means you need to use the same computer for modding, unless that means your school has modding as part of their curriculum which is usually a bad thing as they basically never stay up to date. Regardless, the process should be the same for all operating systems as long as you're using an IDE that has decent Gradle integration, just import the MDK as a Gradle project.

Can you be more specific about "not opening"? Are you prompted to pick a program to open it with? Does it appear in the taskbar but no window opens? Does it open but close again immediately?

Have: 1 . 16 . 5 - 4 . 0 . 1 . 89 Need: 4 . 0 . 0 . 80 1 < 4, check fails because survive did their version constraint wrong and needs to fix it

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Remove Optifine

Multithreading is not a magic solution to lag, there is no magic solution to lag. To be able to give you any more tips I'd need to know the mods you're using and your full system specs, including disk IO, as well as the nature of the lag

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To summarize: If you have Java installed correctly there is no difference to you (both work on double click), but making an exe is extra effort and annoyance for us.

Install Java

If you haven't changed it there's no harm in deleting it

Delete forge-client.toml from your config folder and try again

You're starting a vanilla server, to run a Forge server run the Forge jar

Be more specific Which jar is "the server jar"? How are you running the jar? Through a terminal? By double clicking?

Seems to be hardcoded and I think this could be solved in a better way, I'll look into it

Looks like Ice and Fire uses code that breaks when deobfed to official names, you'll have to use mcp

Looks like a Dynamic Trees issue, check for updates and if there aren't any, provide the log to the devs

Start with removing MixinBootstrap, the version of Forge you're using ships MIxin so there's no need for it and it's just another thing to break

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